An analysis of more than two decades’ worth of supernova explosions convincingly boosts modern cosmological theories and reinvigorates efforts to answer fundamental questions.
A powerful new analysis has been performed by astrophysicists that places the most precise limits ever on the composition and evolution of the universe. With this analysis, dubbed Pantheon+, cosmologists find themselves at a crossroads.
Pantheon+ convincingly finds that the cosmos is made up of about two-thirds dark energy and one-third matter — predominantly in the form of dark matter — and is expanding at an accelerating pace over the last several billion years. However, Pantheon+ also cements a major disagreement over the pace of that expansion that has yet to be solved.
By putting prevailing modern cosmological theories, known as the Standard Model of Cosmology, on even firmer evidentiary and statistical footing, Pantheon+ further closes the door on alternative frameworks accounting for dark energy and dark matter. Both are bedrocks of the Standard Model of Cosmology but have yet to be directly detected. They rank among the model’s biggest mysteries. Following through on the results of Pantheon+, researchers can now pursue more precise observational tests and hone explanations for the ostensible cosmos.
“With these Pantheon+ results, we are able to put the most precise constraints on the dynamics and history of the universe to date,” says Dillon Brout, an Einstein Fellow at the Center for Astrophysics | Harvard & Smithsonian. “We’ve combed over the data and can now say with more confidence than ever before how the universe has evolved over the eons and that the current best theories for dark energy and dark matter hold strong.”
Brout is the lead author of a series of papers describing the new Pantheon+ analysis, published jointly on October 19 in a special issue of The Astrophysical Journal.
Pantheon+ is based on the largest dataset of its kind, comprising more than 1,500 stellar explosions called Type Ia supernovae. These bright blasts occur when white dwarf stars — remnants of stars like our Sun — accumulate too much mass and undergo a runaway thermonuclear reaction. Because Type Ia supernovae outshine entire galaxies, the stellar detonations can be glimpsed at distances exceeding 10 billion light years, or back through about three-quarters of the universe’s total age. Given that the supernovae blaze with nearly uniform intrinsic brightnesses, scientists can use the explosions’ apparent brightness, which diminishes with distance, along with redshift measurements as markers of time and space. That information, in turn, reveals how fast the universe expands during different epochs, which is then used to test theories of the fundamental components of the universe.
The breakthrough discovery in 1998 of the universe’s accelerating growth was thanks to a study of Type Ia supernovae in this manner. Scientists attribute the expansion to an invisible energy, therefore monikered dark energy, inherent to the fabric of the universe itself. Subsequent decades of work have continued to compile ever-larger datasets, revealing supernovae across an even wider range of space and time, and Pantheon+ has now brought them together into the most statistically robust analysis to date.
“In many ways, this latest Pantheon+ analysis is a culmination of more than two decades’ worth of diligent efforts by observers and theorists worldwide in deciphering the essence of the cosmos,” says Adam Riess, one of the winners of the 2011 Nobel Prize in Physics for the discovery of the accelerating expansion of the universe and the Bloomberg Distinguished Professor at Johns Hopkins University (JHU) and the Space Telescope Science Institute in Baltimore, Maryland. Riess is also an alum of Harvard University, holding a PhD in astrophysics.
“With this combined Pantheon+ dataset, we get a precise view of the universe from the time when it was dominated by dark matter to when the universe became dominated by dark energy.” — Dillon Brout
Brout’s own career in cosmology traces back to his undergraduate years at JHU, where he was taught and advised by Riess. There Brout worked with then-PhD-student and Riess-advisee Dan Scolnic, who is now an assistant professor of physics at Duke University and another co-author on the new series of papers.
Several years ago, Scolnic developed the original Pantheon analysis of approximately 1,000 supernovae.
Now, Brout and Scolnic and their new Pantheon+ team have added some 50 percent more supernovae data points in Pantheon+, coupled with improvements in analysis techniques and addressing potential sources of error, which ultimately has yielded twice the precision of the original Pantheon.
“This leap in both the dataset quality and in our understanding of the physics that underpin it would not have been possible without a stellar team of students and collaborators working diligently to improve every facet of the analysis,” says Brout.
Taking the data as a whole, the new analysis holds that 66.2 percent of the universe manifests as dark energy, with the remaining 33.8 percent being a combination of dark matter and matter. To arrive at even more comprehensive understanding of the constituent components of the universe at different epochs, Brout and colleagues combined Pantheon+ with other strongly evidenced, independent, and complementary measures of the large-scale structure of the universe and with measurements from the earliest light in the universe, the cosmic microwave background.
“With these Pantheon+ results, we are able to put the most precise constraints on the dynamics and history of the universe to date.” — Dillon Brout
Another key Pantheon+ result relates to one of the paramount goals of modern cosmology: nailing down the current expansion rate of the universe, known as the Hubble constant. Pooling the Pantheon+ sample with data from the SH0ES (Supernova H0 for the Equation of State) collaboration, led by Riess, results in the most stringent local measurement of the current expansion rate of the universe.
Pantheon+ and SH0ES together find a Hubble constant of 73.4 kilometers per second per megaparsec with only 1.3% uncertainty. Stated another way, for every megaparsec, or 3.26 million light years, the analysis estimates that in the nearby universe, space itself is expanding at more than 160,000 miles per hour.
However, observations from an entirely different epoch of the universe’s history predict a different story. Measurements of the universe’s earliest light, the cosmic microwave background, when combined with the current Standard Model of Cosmology, consistently peg the Hubble constant at a rate that is significantly less than observations taken via Type Ia supernovae and other astrophysical markers. This sizable discrepancy between the two methodologies has been termed the Hubble tension.
The new Pantheon+ and SH0ES datasets heighten this Hubble tension. In fact, the tension has now passed the important 5-sigma threshold (about one-in-a-million odds of arising due to random chance) that physicists use to distinguish between possible statistical flukes and something that must accordingly be understood. Reaching this new statistical level highlights the challenge for both theorists and astrophysicists to try and explain the Hubble constant discrepancy.
“We thought it would be possible to find clues to a novel solution to these problems in our dataset, but instead we’re finding that our data rules out many of these options and that the profound discrepancies remain as stubborn as ever,” says Brout.
The Pantheon+ results could help point to where the solution to the Hubble tension lies. “Many recent theories have begun pointing to exotic new physics in the very early universe, however, such unverified theories must withstand the scientific process and the Hubble tension continues to be a major challenge,” says Brout.
Overall, Pantheon+ offers scientists a comprehensive look back through much of cosmic history. The earliest, most distant supernovae in the dataset gleam forth from 10.7 billion light years away, meaning from when the universe was roughly a quarter of its current age. In that earlier era, dark matter and its associated gravity held the universe’s expansion rate in check. Such a state of affairs changed dramatically over the next several billion years as the influence of dark energy overwhelmed that of dark matter. Dark energy has since flung the contents of the cosmos ever farther apart and at an ever-increasing rate.
“With this combined Pantheon+ dataset, we get a precise view of the universe from the time when it was dominated by dark matter to when the universe became dominated by dark energy,” says Brout. “This dataset is a unique opportunity to see dark energy turn on and drive the evolution of the cosmos on the grandest scales up through present time.”
Studying this changeover now with even stronger statistical evidence will hopefully lead to new insights into dark energy’s enigmatic nature.
“Pantheon+ is giving us our best chance to date of constraining dark energy, its origins, and its evolution,” says Brout.
Reference: “The Pantheon+ Analysis: Cosmological Constraints” by Dillon Brout, Dan Scolnic, Brodie Popovic, Adam G. Riess, Anthony Carr, Joe Zuntz, Rick Kessler, Tamara M. Davis, Samuel Hinton, David Jones, W. D’Arcy Kenworthy, Erik R. Peterson, Khaled Said, Georgie Taylor, Noor Ali, Patrick Armstrong, Pranav Charvu, Arianna Dwomoh, Cole Meldorf, Antonella Palmese, Helen Qu, Benjamin M. Rose, Bruno Sanchez, Christopher W. Stubbs, Maria Vincenzi, Charlotte M. Wood, Peter J. Brown, Rebecca Chen, Ken Chambers, David A. Coulter, Mi Dai, Georgios Dimitriadis, Alexei V. Filippenko, Ryan J. Foley, Saurabh W. Jha, Lisa Kelsey, Robert P. Kirshner, Anais Möller, Jessie Muir, Seshadri Nadathur, Yen-Chen Pan, Armin Rest, Cesar Rojas-Bravo, Masao Sako, Matthew R. Siebert, Mat Smith, Benjamin E. Stahl and Phil Wiseman, 19 October 2022, The Astrophysical Journal.
the DUH scientists refuse to consider INERT HYDROGEN as dark matter (although the percentage is spot on) and dark energy as equal to what is released by atomic Hydrogen collapsing to an inert lower state. cf. http://www.brilliantlightpower.com
Or as there is more space outside a gravity well gaseous dark matter expands to its maximum. Just like a ballon continues to expand until all of the gas in the cylinder vaporizes or the ballon pops.
Idiotic theories of Dark Matter and Energy are glaring proof that modern Theoretical Physics is a fraud and a swindle and these Physicists are as crooked as a BC highway, since the Halflec Model of subatomic structure answers all these questions and much, much more. Modern Theoretical Physicists are swindlers that don’t want the public to know the truth about science and the universe. There are no mysteries with the Halflec Model but these crooks don’t want the public to know the truth because then they couldn’t swindle you and live the good life at your expense.
Your meds are in the top drawer on the right….
“We’ve combed over the data and can now say with more confidence than ever before how the universe has evolved over the eons and that the current best theories for dark energy and dark matter hold strong.”
Really? Who wrote this? Dark energy theory is even stronger now even though there is no explanation for it at all? What sense does that make?
Dark matter theory is even stronger than ever? How? What is it made of? What role does it have in our universe? Nothing at all?
Dark matter is an extremely pressurized, absolute zero field of sterile electron neutrinos. All energy including all the forces are a manipulation of this field with energy. Black holes use this field as the catalyst when quarks are separated from a sufficient enough reaction. The strong force is between quarks and the sterile electron neutrinos. When quarks get separated from a sufficient enough reaction, it is the sheer density and pressure of space that is able to keep the quarks apart indefinitely. As a result, this plasma creates the most powerful electromagnetic radiation in the universe which are gamma rays. That’s what black holes are and that’s how they use space as the limitless catalyst a reaction like fusion should have but doesn’t.
Dark energy is simply momentum the galaxies obtained when the Big Bang happened. The galaxies are shrapnel from our universe turning itself into a gargantuan particle collider. The reason science thinks the universe is accelerating in its expansion is an optical illusion from mistakenly assuming that the universe itself is expanding. The collision created an anisotropic expansion of matter that looks like an accelerating expanding universe when really it isn’t.
How is science ever going to figure anything out if it keeps using the same, worthless theory it has used for decades?
Write your own paper and submit it. If you’re that confident about your veracity you’ll win a Nobel Prize
Who’s going to listen? When you submit a paper for “peer review”, what do they want to hear? Do you ever read the papers? All that these papers ever accomplish is explaining how current theories don’t work. What good is that? I actually have a theory that explains our universe by law but it doesn’t follow the Big Bang theory. So, it gets rejected. The scientific community is positive the Lambda-CDM model is a fact and it is determined to use this horror of a theory to figure out the problems when it has been worthless for decades. The Nobel prize should be called the “Make sure you use the Big Bang theory” prize. Regardless of how many problems continue to be found, the goal of this prize is to make sure that everything known to science currently is not thrown in the dumpster where it should be. “Dark matter” and “dark energy” are not explanations for anything but just words of confusion. Why do you think Hawking never got one? It’s because he knew black holes must emit energy like every other star in the universe. Unfortunately, because of the completely factual Big Bang theory and its ridiculous claim that black holes emit absolutely nothing, Hawking never got a Nobel prize because he contradicted the “definition” of black holes.
That is exactly the wrong approach to scientific commentary. It sounds more like emotion-based vilification, hyperbole and conspiracy theory than a rational, fact-based refutation.
What “facts” are you talking about? The dark matter “fact”? The dark energy “fact”? Do you consider these terms explanations? That’s what it seems like.
What about the “fact” that the first law of thermodynamics doesn’t allow a universe to be “born”? What about the fact that the second law of thermodynamics doesn’t allow a harmless cloud of gas and dust to turn itself into a star that will burn for billions of years?
That’s the problem with people that leave comments like your’s Bob. You have been trained to ignore all the problems that exist. Trained to assume that current theories work just fine. You don’t notice articles like the recent one where scientists have no idea what is going in inside an atom. You don’t pay attention to to the muon magnetic moment problem that refutes the standard model. Your comment is the kind of thought process all the great scientists in the past that discovered something important had to go through. You would have never believed Galileo when he said the Earth wasn’t the center of the universe. Instead, with your attitude, you would have wanted him to be burned at the stake. He was almost murdered until he retracted his thoughts because the church told him he better. Fortunately for him, he was only put under house arrest the rest of his life.
Did any of that get through?
they have no new ideas, just that there is something out there that runs the cosmos, but they have no idea what it really is….we need some more einstein brains to move the theory along….
The “Big Bang” was simply our universe turning itself into a gargantuan particle collider. The only difference is the size of the “particles” involved and the size of the “shrapnel”. It wasn’t gravity that created all the energy we see. That’s why science has no chance to understand quantum gravity. Everything was already here when the Big Bang happened. That’s what the first law states it was like. The galaxies are expanding because they are shrapnel. The only reason science thinks the universe is accelerating in its expansion is because the collision created an anisotropic expansion of matter that will appear to be an accelerating, expanding universe if it is mistakenly assumed that the entire universe is expanding.
It all started when the priest Georges Lamaître took Hubbles expanding galaxies and turned it into his own Genesis by making the universe expand. Hubble and many of his peers wanted nothing to do with this law-obliterating theory. Science has conveniently erased this fact from the conscious of the scientific community. Einstein is in on it as well because he initially condemned Lemaîtres assumption by calling its physics “abominable”. Even after that statement, he still accepted the Big Bang theory. That’s why he had no chance to figure out quantum gravity the last half of his life.
They don’t even know where those space-time maps they use come from or what they actually mean. They all use them, but they don’t have a clue that they are black hole embedding diagrams turned on their side to show that the Z-axis of the Einstein-Rosen bridge becomes the time-like dimension in the daughter universe. Andrei Linde ripped off my maps for his copycat theories, took them out of context. Aye, your big time physicists and cosmologists are typically liars and thieves. Not too bright, either. Charge warps space-time by creating an energy-density gradient, gravity is corpuscular radiation that replaces energy the nucleus loses in enhancing the energy-density of space-time through charge. Maxwell didn’t define the couriers of the charge force. Einstein mistook the ether drag as an effect of gravity. Until these doctrinaire @ssholes die, we’ll be saddled with their vanity and inability to admit they might have made a mistake or two in their interpretations.
I was wondering if the “invisible” mass implied by the big bang theory could simply be mass that has obtained a relative velocity greater than c, making their wavefronts unable to intersect with our observations.
The observation of x-ray “lattices” makes me wonder if the observed acceleration, while originally driven by energetic expansion, might be derived from the gravitational effect of these lattices. So, the most external mass is “falling” towards a gravity well that exists outside our perceived photonic bubble.
Just an idea, not sure how you would test it.
Dark Matter and Dark energy are just bad scientists trying to cover the fact that they don’t understand the universe. True scientists are ok stating they don’t understand it all. It’s the ones who strive to be experts instead of scientists who make up these contrivances
Everybody has their “thing”, in this case it’s Pantheon+. I like the possible explanations for Dark Energy and Dark Matter from a view of String Theory.
For Dark Energy, all matter and energy, including photons (light), have vibrating strings as their basis.
String and anti-string pairs are speculated to be created in the quantum foam, a roiling energy field suggested by quantum mechanics, and they immediately annihilate each other. If light passes near these string/anti-string annihilations, perhaps some of that annihilation energy is absorbed by the string in the light. Then the Fraunhofer lines in that light will move a bit towards the blue and away from the red shift. As this continues in an expanding universe we get the same curve displayed by Perlmutter and colleagues at their Nobel Prize lecture, without the need for Dark Energy.
This speculation has the universe behaving in a much more direct way. Specifics on this can be found by searching YouTube for “Dark Energy – a String Theory Way”
For Dark Matter, a view of String Theory suggests it appears to us as an effect of string/anti-string annihilations. As you may know, quantum mechanics requires that strings and anti-strings are surrounded by “jitters” that reduce their monstrous vibrating energies. What if this jitter remains for a fraction of an instant after their string/anti-string annihilations? This temporary jitter would be seen by us as matter, via E=mc2, for that instant before it too returns to the foam. That’s why we never see it – the “mass” lasts only for that instant but is repeated over and over and over, all over. Specifics on this can be found by searching YouTube for “Dark Matter – A String Theory Way”
From previous articles:
In 2019, the researchers launched an experiment at Canada’s national particle accelerator facility, TRIUMF, looking for that very hypothetical decay. And they did find a decay with unexpectedly high probability, but it wasn’t a dark decay.
It looked like the beryllium-11’s loosely bound neutron was ejecting an electron like normal beta decay, yet the beryllium wasn’t following the known decay path to boron.
So Does this Mean we are Likely heading into a Black hole ??? If we were, the News would Never let us Know about that, World Economic Chaos Etc. The Book of Revolation Last Signs Definitely Says that we will enter a Black hole.
As I’ve commented in different terms multiple places and times before, I find there’s a basic flaw in physics since Einstein’s very ‘insightful’ E=MC2. Proved by double-slit experiments and light slowing in different mediums on earth, and gravity lensing in deep space, photons can be influenced by single lines of pulsing or vibrating lines of gravity force causing them to accelerate (blue shift) when leaving their sources and decelerate (red shift) when arriving here on earth. Furthermore, having proved to myself time and again that ‘rotation’ can increase the effective gravity of an object, rotation and ‘spin’ can probably account for the misconceptions of quantum mechanics, dark energy and dark matter. Ineligible for any research grants as only a lone lay experimenter may I suggest the professional research be turned to trying to determine the true age and size of the universe; no less a monumental task for a global aggregation of eager physicists?
It’s hilarious to read so many clueless attempts to discuss and debunk actual science from actual scientists. This is the same problem that the public discussion of Covid and vaccines has, only in that case, lots of people get sick and die as a result of believing blather. (And that poor boy with polio will be crippled all his life, if he lives.) Hopefully a renewed respect for science, and for each other, will develop after Rumpism is dead.
Complete your research, Rich, and you should find that the total number of US deaths attributed to Covid-19 (e.g., Covid-19 ‘scamdemic’) is about the same as we could expect of too-common medical errors in the same time frame. And, check out Dr. Sam Bailey (NZ) on polio, DDT and the John D. Rockefeller Foundation. Individual doctors and scientists may be doing their best but they’re both seriously handicapped with structurally weak foundations (e.g. me, above).
These results may be misunderstanding the situation by presuming a solution comprised solely of dark matter and energy (plus ordinary matter). Recent work in turbulent plasmas (like that in hot interstellar space) can provide much of the same effects and the imagined dark matter, for instance.
Dark Matter and Dark Energy aren’t specific things, they’re parameters that some thing or some things must exhibit under the conditions given. It’s simpler to assume one thing for each, but it may be the interplay of many things. All we have are parameters.
Dark matter isn’t inert hydrogen or sterile neutrinos. (Sterile neutrinos don’t exist, for a start.) Dark Energy isn’t momentum. Which confirms my long-held theory that you don’t find answers to cosmological questions in the comments.
I assume cosmologists have considered whether the Hubble Constant is actually a variable changing with time, and also assume that particle physicists who can reproduce the physics of the CMBR would have said if the physics suggested unexpected or unexplained forces that might account for the Tension.
However, they may lack sufficient data to be able to model this well enough. If the error bars swamp the signal, they won’t know if they’re plotting a consistent point, a curve, or the words to a pop song. We have to trust they know what they’re doing, even though that can be difficult.
My big concern is that it’s presented as if scientists are looking at each option in turn rather than eliminating entire classes of possibilities.
This matters. Let’s say there’s a billion possible explanations. Checking one at a time takes a billion experiments. Eliminating half the remaining options each time would require 30 experiments.
A huge difference. And scientists know all about binary searching problem spaces. Even in the late 1800s, it was well known that was how you solved problems quickly.
Assuming that scientists aren’t being reckless, I’d like to see more written about how scientists are in fact approaching the problem.
Oy! 23 comments and none were discussing the science of the paper.
Can someone Please provide me with the same author of this article? I am struggling to find it and I need it for a project. Thanks!